[FL-3786] Fixed infinite loop in dictionary attack scene

[RebornedBrain]

What's new

• Previously when choosing 'Unlock with dictionary' several times it required to repeat 'Exit' sequence also several times due to the issue that same scene was added to scene manager multiple times.

Verification

1. Read MIFARE Classic
2. Skip dictionary attack
3. Choose 'More' -> 'Unlock with dictionary'
4. Goto to step 2

Actual result: It requires to repeat 'Back' operation several times until it will go back to NFC menu
New result: On pressing 'Back' button Flipper will move back to NFC menu

Checklist (For Reviewer)

• PR has description of feature/bug or link to Confluence/Jira task
• Description contains actions to verify feature/bugfix
• I've built this code, uploaded it to the device and verified feature/bugfix